Improvement in millstone-balances



- WILLIAM A VANCE.

improvement in Millstone-Balances.

N0. "4,890. Patented May16,187l.

. AMFMOIU'HMOGRAPH/C ca )1). IOSEDENL'LS PROCESS) new tem.

GEORGE THOMAS CLARK, OE KALAMAZOO, MICHIGAN, ADMINISTRATOR. OF WILLIAMA. VANCE, DECEASED.

Letters Patent No. 114,890, dated May16, 1871'.

. IMPROVEMENT IN MlLLSTONE-BALANCES.

The Schedule referred to in these LettersPatent and making part of theaame.

I, GEORGE THOMAS CLARK, of Kalamazoo, in the county of Kalamazoo andState of Michigan, administrator of the estate of WILLIAM A. VANCE, ofsaid village and county, deceased, present the following specificationof Improvements in Balancing Millstones, the invention of said WILLIAMA. V NCE,

Nature and Object of the Invention.

This invention relates to the combination and connection, with one ormoreof screw-clamping bands, (to encircle and secure the periphery of arunner millstone,) of a weight-receiving box, having several com.-

partments arranged circumferentially to receive thebalancing-weights,the object being to facilitate the applicationand concentration of thecounter-balance at the precise point where itis needed, after the bandscarrying such weight-receiving boxes have been approximately adjusted,fitted, and clamped around the runner-stone, as will hereinafter morefully appear.

Description of the Accompanying Drawing.

Figure 1 is a perspective view of a runner millstone carrying oneclamping-band, with weight-receiving box attached.

Figure 2 is a similar view of the box connected to a broken section ofthe bandon an enlarged scale.

Figure 3 is' a cross-section of the weight-box and band, with slidingclasp attached.

General Description. A is the runner millstone, and

b b are top and bottom hoops or bands of the ordinary kind;

B represents one of the screw-clamping bands.

'C is one of the balancing weight-boxes riveted to the band B, or soconnected by a sliding clasp, it, as to permit the boxes to be adjustedcircunlferentially on the bands when slackened.

The bands B may be tightened up by the rightand-left-threadedtightening-bolt t, tapped into anglenuts or cars it, riveted to the,endsof the band, as shown, or by a common nutted' bolt passing through saidears.

. The weight-boxes Gare usually cast in thinnish metal, with curvedsides, the concave or inner side to match the convexity of the band, andthe convex side to clear the concave inner surface of the curb, for thesaid boxes must run in the annular space between the side or edge of thestone and its curb, without touching the latter.

The interiors of the boxes are divided by partitions cinto'severalcompartments, in order that when. the

said boxes are adjusted by their bands on the. stone, and are loaded bythe placing of weights in the central compartments, so as to bring thestone to a standing balance as near as may be, then the boxcarryingbands may be raised or loweredon the stone,

' the weights moved from one compartment to another,-

and also increased ordiminished in such compartment at pleasure, untilexperimental trials by running the'stone up to speed shall prove it tobe in exact running balance.

Although in the case of a well-constructed stone, truly hung, but asingle weight-box may be required to put such stone in running balance,as shown in v the drawing, it must not be inferred that this inventionis limited to but one, for there are many stones that will need morethan one hoop so weighted,'and perhaps more than one weight-box to eachhoop.

- The general rule is that where a stone is out of balance at but onewell-defined point, and that point is in some horizontal plane betweenthe point of suspension on the cock-head of the spindle and the grindingface of the stone, then such stone maybe put in correct running balanceby a corresponding counter-balance placed exactly opposite in a radialline, and in the same plane.

If a stone is so constructed that the over-balance is either wholly orpartially in a plane above that of suspension, and is not confined toone point, then more than one weight-box will be needed, and they mustbe placed at such circumferential points in such planes, and soweighted, as not merely to establish a standing balance, but tocounteract the tendency which centrifugal force (generated by the stonesrotation) exerts to make the plane of preponderating gravitycoincident'with the plane of suspension. Balancing-weights of lead inthe form of crescents, placed between the hoop 'and runner, have beenused before. But in this mode of application it is extremely diificultto get the correct running weight, and such weight is diffusednecessarily over too large a portion of the circumference of the stone.

The weight-boxes U have certain advantages over other modes. They arecheaply constructed, readily applied to the stone, and, as faras-'thei1"gravity goes,

aid in balancing. I

When once placed in approximately correct position at the periphery ofthe stone the miller can readily balance it-with great exactitude torunning speed by raising or unscrewing and removing the cover E, withwhich the box is provided, removing part of the contained weights, oradding more, as required, sliding the box along the hoop by its clasp toadjust it,

if secured in thatway, or moving the weights in the box from one toanother of the compartments.

When the weights are so adjusted in the boxes that the stone runswithout jar and wabhle, the covers E may be replaced to secure theweights and enable the stone to be turned for dressing without spillingthe said weights.

I claim- The adjustable box 0, divided into separate compartments bypartitions e, and provided with the hook (I, in combination with theclamping-band 3, all constructed, arranged, and operating substantiallyin the manner described.

GEO. THO.- CLARK,

' Administrator.

WVitnesses M. W. Bonnows, WILLIAM FLETCHER.

